Trigonometry problems for NYSE regents

[priscilla98]

Homework Statement

In the diagram below, KW = 6, Kt = 5 and m<KTW = 90. What is the measure of angle K, to the nearest minute? Below is the website for this question because this is one of the questions from the algebra 2 and trigonomentary. This is question 23.

http://www.nysedregents.org/a2trig/20100615exam.pdf

Homework Equations

SOH CAH TOA

The Attempt at a Solution

I know if you use the inverse of cosine in this problem you can get the degrees of K. For ex, cos (inverse) (5/6) = 33 degrees but I'm confused on how to get the minutes.

 

[Mentallic]

You need to obtain more accuracy from the value of cos^{-1}(5/6)

Your calculator display should give something like 33.55730976 if set to degrees. A minute (denoted by ') is defined as being 1/60 of a degree, so 33^o30' is the same as 33.5^o because 30 is half of 60.
33^o45'=33.75^o

etc.

Your calculator should have a button that can convert decimals to minutes and seconds (a second is a 60th of a minute - thinking of degrees as being hours should make it easily memorable), but if you can't find this button, it can quickly be done with a bit of thinking.

We have 33.55730976 and we need to convert this into the form 33^ox' to the nearest x. So all we have to deal with is the 0.55730976. Since a minute is 1/60 of a whole, then we have x/60=0.55730976. Now you have your minutes after you round off

 

[priscilla98]

Thanks a lot. have a good day :)

 

[Mentallic]

You too priscilla